1. Field of the Invention
The present invention relates to an electrophotographic processor using a laser beam scanning unit (LSU) as an optical source, and, more particularly, to a method of reducing consumption of a developer used in an electrophotographic processor by adjusting the power of a laser beam to correspond to a set density of an output image.
2. Description of the Related Art
FIG. 1 is a diagram of a general electrophotographic processor including a charging unit 10, a laser exposure unit 20, a photosensitive object 30, a developing unit 40, and a transferring unit 50.
The photosensitive object 30 is charged with electricity by the application of a high negative voltage by the charging unit 10. An exposure process is performed on the photosensitive object 30 using a laser beam emitted from the laser exposure unit 20 in order to form a latent electrostatic image thereon. The developing unit 40 adheres a developing solution to the latent electrostatic image formed on the photosensitive object 30 to form a visual image on the photosensitive object 30. The transferring unit 50 transfers the visual image formed on the photosensitive object 30 to paper S.
There are various methods of reducing consumption of a developer in the above electrophotographic processor. These methods are: (i) modulating a pulse width to reduce the pulse width of a print data signal; (ii) reducing a developing bias voltage applied to the developing unit so as to apply less developer; and (iii) lightly outputting an image using a dithering technique.
However, method (i) of reducing a pulse width of print data increases a radiation rate of an electromagnetic interference (EMI) of an electrophotographic processor, method (ii) of reducing a developing bias voltage pollutes a non-image region of an output image with a developer, and method (iii) of using the dithering technique lowers the resolution of an output image.